Check mechanism



W,12,.1940. DAWS P 2,220,994

, v CHECK MECHANISM .Filed July 14, 1937 lsq v )FIGB 9 INVENTOR.

A TTORNE V 5.

ERNEST DAVIS Patented Nov. 12, 1940 PATENT OFFICE n f,2,220,99 4. CHECK MECHANISM Ernest Davis, Syracuse, N. Y.,..assignr to The Prosperity 0on1pany, lnc., Syracuse, N.. Y., a corporation of. New York ApplicationJuly14,1937,"Se1ial'No. 153,589 6 Claims. n (01. 18'8'- 97) This invention relates to checks or check mechanisms, particularly for checking movements in opposite directions or back'andforth movements, as for instance, for checking machines having an operating movement in reverse directions dur ing each cycle of operation, as an opening and closing movement, for checking or absorbing the shocks, as the machineapproa'ches the end of its closing movement and as it approaches the end of its opening movement, and has for itsi object means operableto vary the checking eifect during different periods of the cycleiof movement of the check mechanism; I

It also has for its object a check mechanism involving a piston having a back and forth' move ment in a piston chamber and making a complete back and forth movementfusuallya reciprocation, during each cycle of movement of the check mechanism, and a check valve through which a hydraulic liquidis forced during the checking operation, with means actuated automatically during the operation of :the checking device for varying the openingof the checkvalve,

and hence, varying the checking 'efiectduring diiferent periods of the cycle of movement of the piston member, so that, in a machine having an T opening and closing movement; the piston m akesone back and forthv movement ,or one complete reciprocation during the openingmovement and 3 during the closing movement of the machine. The check mechanism may be adjusted to give a The invention consists in the novel features and in the combinations and constructions here-i inafter set forth and claimed.

In describing this invention, reference is had to the accompanyingdrawing in which like characters designate corresponding parts in all the V1 GWS Figure 1 isa side elevation, partl ybroken away, of a check mechanism embodying this invention. on line 2--.2, Fig: I

Figure 2 is a sectional view ure 1.

Figure 3 is a plan view of parts seen in'Figure 1, the cap of the casing being omittedand v parts being shown in section.

Figures 4, 5 and 6 are diagrammatic views il lustrating the positions of the parts .of. the check mechanism when respectively in starting posi-- tion, in an intermediate position,.and in com-- pletely operated position.

'12, .1937, now Patent No; 2,138,372 issued Nov. 29,

more specific ,objects will appear The invention is here shown as embodied in the sametype of check mechanism as that shown in my application, Serial Number 147,993, filed June 1938, and thepi'ston chamber is a cylinder, and the'piston reciprocatesin the cylinder.

I designates the casing, which includes a lower section 2 and an upper section or removable cap 3, the lower section 2beingprovided with an oil reservoir 4, and in this reservoir is located or 10' formed a piston chamber or cylinder 5, with a' passage or by-pass 6" connecting the upper portion I of the'reservoir and the lower portion 8 around one side of the cylinder 5. The casing has a gage or sight-glass G for indicating the oil level.

9 designates a" reciprocating pump piston or plunger in the cylinder 5.

.IO designates a crank shaft journalled'in the casing outside the reservoir 4, here shown as above the level L of the oil therein. The motion transmitting means between the piston 9 and the crankshaft is preferablyia connecting rod I l pivoted at its lower end to the piston and mounted at I3 on the crankof the crank shaft, The connecting rod extends out of the reservoir dzabove the liquid therein. The crank shaft is mounted in bearings l4 located between the sections 2', '3 of the casing and entirely out of or above the oil in the reservoir, and hence out of the pressure ab'i area.

l5 designates a reversely movable actuator, asa lever arm, having a back and forth movement, as ,an oscillating movement, the lever l5being shown as mounted on a shaft l6 journalled in bearings provided on a suitable bracket I! on the outside of the casing. The reduction leverage mechanism between the arm l5 and the crank shaft [0 preferably consists of gears l8 andl9 keyed respectively on the shaft [6 andthe shaft 40*: I0 outside of the casing/l. The gear I8 is of larger diameter than the gear l9 and the gear reduction issuch, or the gears of such sizes as to provide a' leverage ratio of slightly greater than two to one. The ratio issuch that the piston makes a complete reciprocation or an out" and in stroke; upon ,movement of the arm 15 in one direction from starting position and one reciprocation or two strokes upon each movehence at one side of the dead center line, intersecting the axis of the crank shaft l and the axis of the pivot connecting the rod II to the piston. As the arm l moves outwardly from its starting position, the piston moves on its out stroke, and when it reaches the end of its out or up stroke it is in the radial .position illustrated by the line B (Figure 1), and during continued movement of the arm l5 in the same direction, the piston remains substantially practically stationary while moving from the radius B to radius C (Figure 1), and then during continued movement of the arm I5 in the same direction, as indicated by the arrow, Figure 1, the piston moves on its in stroke to the lower end of the cylinder 9 and the crank moves into an angular position, illustrated by the radius D (Figure 1). During this movement, the arm l5 has moved through an angle of approximately 130, and the crank of the shaft is moved through an angle of approximately 232. During the return movement of the arm [5 to starting position, the shaft I9 is shifted reversely in the same manner, and the piston 9 likewise makes a complete re- 2 ciprocation, or an out or fup stroke and an 'in or down stroke, and'in the direction of the arrows in Figures 6 and 5 from the position shown in Figure 4.

The cylinder 5 is formed with a port in the ;outer end portion thereof,'and preferably in the head therof, which head-is spaced from the bottom-of the reservoin'so that the port opens into the lower portion 8 of the reservoir.

2| designates a'port, and 22 a check valve for 35Qcontrolling said port, the check valve being here shown as having a stem 23 guided in a suitable bushing 24 suitably supported by a spider 25 in the port 2|, the stem extending through the port into the lower portion 8 of the reservoir. This idbivalve 21 is adjusted to open different distances from its seat. It is operated in synchronism with the movement of the piston 9 from any suitable moving part of the check mechanism, as for'instance, the crank shaft l0, and suitable connec- 45Ztions operated by the crank shaft; These connections include cams 2B, 21' actuated by the crank shaft, and here shown as mounted on an extension Ill thereof, outside of the casing, a shaft 28 journalled in the lower portion of the casing and extending into the lower portion 8 of the reservoir and provided with a connection, as a cam 29, for coacting with the lower end of the stem 23 ofthe valve 22 and motion transmitting connections extending outside the casing, as a 5 I 1ink 30 having a follower or roller 3| at one end coacting with the cams 26 and 21, and also being connected at its other end to an arm 32 on the shaft 28, it'being connected to the arm 32 by a sliding or pin-and-slot connection. The cams 60 26, 21 are adjustable into different radial angles relatively to each other and the crank shaft, and are held in their adjusted position in any suitable manner, as by set screws 33, extending radially into the hubs of the cams against the extension Ill of thhe crank shaft 10. The roller 3| is caused to follow the cams 26, 21 by a suitable spring 31 acting on the 'rod 39. The cam 29 is of such contour as to not permit the valve head 22 to entirely seat, so that the flow of oil 'from the piston chamber 5 past the valve is not entirely obstructed, whenthe valve head 22 is in its lowermost position.

In operation, during eachfout or up stroke l of the piston 9, the oil in the reservoir readily 75 transfers through the bypass S'into the cylinder below the piston and flows up through the port 2 I, past the valve 22, which opens freely and is not retarded in its opening movement by the cam 29, and during the in or "down stroke, the valve 22 is held by the cam 29 off its seat an amount corresponding to the adjustment of the cam, so that the resistance offered to the flow of the oil past the valve, or the checking effect is determined by the position of the valve 22. During the period that the piston is reversing itself at the end of the ou stroke and at the beginning of the in stroke, there is, in this embodiment of my invention, practically no checking effect, because the piston is practically stationary while the crank is traveling from the point B to the point C, or vice-versa. The pison 9 makes one reciprocation or one up and down movement during the movement of the actuator l5 from the position shown in Figure 4 to that shown in Figure 6, these being the positions occupied when the machine, having an opening and a closing movement, as a press, is in open position and in closed position, respectively, and during this movement, one of the cams 23 or 21 controls the movement of the valve 22. During the movement of the piston 9, when the actuator I5 is in the position occupied in Figure 6 and moved to that shown in Figure 4, the piston makesa complete up and down movement, while the machine or press, having an opening and aclosing movement, is going from closed to open position, and the other of the cams then controls the movement of the valve 22, so that a different checking effect, if desired, may be had during the opening movement of the machine or press.

In Figure 5, the actuating element or arm l5 isshown in its position occupied when the piston is approaching the end of its up stroke or approaches the beginning of its reversing movement, when it is practically at a standstill. During movement of said arm from the position shown in Figure 4, to that shown in Figure 6, the connecting rod is passing through the dead center line or between radial lines BC (Figure 1), that'is, a line passing through the axis of the crank shaft and the point of connection of the connecting rod to the piston.

Owing to the adjustable cams 26, 21, the check valve 22 may be adjusted to open to a greater or less degree during the cycle of movement of the piston, and hence, vary the checking effect during different periods of the cycle of movement of the piston. One of the cams 26, 21 controls the cycle of movement while the machine to which the checking device is applied, is closing, and the other controls the checking efiect during the cycle of movement of the piston, while the machine is opening.

What I claim is: a

1. In a check for checking movements in onposite directions, a casing formed with a reservoir for a liquid, a piston chamber communicating with the reservoir to receive liquid therefrom and discharge .the same thereinto, the chamber having a port opening into the reservoir, a piston having a back and forth movement in the piston chamber, a check valve in the port, a rock shaft, means connecting it to the piston for transferring the motion thereof to the piston and effecting a complete back and forth movement upon rocking of the rock shaft in one direction and a complete back and forth movement upon rocking of the rock shaft in the other direction, an actuating element connected movable in the cylinder, a check valve in the port, a crank shaft mounted in'the casing, a connecting rod between the crank thereof and the piston, a rocking actuator for the crank shaft and connected thereto to rock the same and effect a complete back and forth reciprocation of the piston during rocking movement of the actuator in one direction, and a complete back and forth reciprocation during rocking movement of the actuator in the opposite direction, and means for controlling the operation of the check valve including a plurality of cams on the crank shaft arranged in different angular relations to the crank shaft, an actuator for the check valve, and motion transmitting connections between the cams and the check Valve actuator, one cam being located to control the check valve actuator during the reciprocation of the piston during rocking movement of the crank shaft in one direction, and the other cam to control the check valve actuator during reciprocation of the piston during rocking movement of the crank piston having a back and forth movement in the chamber, a rock shaft supported in the casing out of the reservoir, connections between the shaft and the piston member to actuate the piston member, a reversely movable actuating element for connection to a moving part to be checked, motion, transmitting means between the actuating member and the shaft, and motion transmitting means between the shaft and the check valve, the latter motion transmittin means including adjustable parts for varying the operation of the check valve to vary the checking effect during different portions of the cycle of movement of the piston. I

4. In a check for checking movements in opposite directions, a casing formed with a reservoir for a checking liquid, and a piston chamber located in the reservoir below the level of the liquid therein and having a port opening into the lower section of the reservoir, the chamber also having communication with the upper portion of the reservoir, a check valve in the port, a piston having a back and forth movement in the chamber, a rock shaft supported in the easing out of the reservoir, connections between the shaft and the piston member to actuate the piston member, a reversely movable actuating element for connection to a moving parttobe checked, motion transmitting means between the actuating member and the shaft, motion transmitting means between the shaft and the check valve, the latter motion transmitting means including adjustable cams for varying the operation of the check valve to vary the checking effect during different portions of the cycle of movement of the piston I 5. In a check for checking movements in opposite directions, a casing. formed with a reservoir for a checking liquid and with a cylinder in the reservoir arranged to be immersed in the liquid, the cylinderhaving a port in its outer end portion opening into the lower portion of the reservoir, a piston workingin the cylinder, a crank shaft journalled inthe casing outside of the reservoir, a connecting rod between the piston and the crank shaft and extending out of the reservoir, an actuating member having a back and forth movement for connection to a part to be checked, and a reduction leverage mechanism between the actuatingmember and the crank shaft to cause the piston to make a complete reciprocation during the movement of the actuating member in one direction, and a complete reciprocation during the actuation of said member in the opposite direction, a check valve in said port, connections between the rock shaft and the check valve for operating the same..- i I 6. In a check for checking movements in opposite directions, a casing formed with a reservoir for a checking liquid and with a cylinder in the reservoir arranged to be immersed in the liquid, the cylinder having a port in its'outer end portion opening into the lower portion of the reservoir, a piston working in the cylinder, a crankshaft journalle'd in the casing outside of the reservoir; a connecting rod between the piston and the crank shaft and extending out of the reservoir, an actuating member having a back and forth movement for connection to a part to be checked, and a reduction leverage mechanism between the actuating member and the crank shaft to cause the piston to make a complete reciprocation during the'movement of the actuating member in one direction, and a complete reciprocation during the actuation of said member in the opposite direction, a check valve in said port, connections between the rock shaft and the check valve for operating the same, said connections including cams on the shaft adjustable into different radial angles to vary the .check-, ing effect during different periods of the cycle of movement of the piston.

ERNEST DAVIS. 

